Digital lighting technologies such as light-emitting diodes (LEDs) offer significant advantages over incandescent and fluorescent lamps. These advantages include, but are not limited to, better lighting quality, longer operating life, and lower energy consumption. Consequently, LED-based lamps are increasingly being used to replace legacy light sources in popular conventional lighting fixtures such as can-type light fixtures. However, a number of design challenges and costs are associated with replacing traditional lamps with LED illumination devices. These design challenges include thermal management, installation ease, and manufacturing cost control.
When an LED operates in a high-temperature ambient environment and/or a space-limited enclosure, the heat generated by an LED and its attending circuitry can cause overheating and premature failure of the LED. Thermal management describes a system's ability to draw heat away from an LED. Passive cooling technology, such as a heat sink thermally coupled to a digital device, may be used to transfer heat from a solid material to a fluid medium such as, for example, air. To prevent overheating of the LED, a heat sink must be designed to absorb and dissipate heat at a sufficient rate with respect to the amount of heat being generated by the LED. If the heat sink does not have the optimal amount of capacity, the heat can gradually build up behind the LED and cause damage to the components.
Retrofitting legacy lighting systems with digital lighting technology also introduces installation challenges. For example, by the very nature of their design and operation, LEDs have a directional light output. Consequently, employing LEDs to produce light distribution properties approximating or equaling the light dispersion properties of traditional lamps may require the costly and labor-intensive replacement or reconfiguration of the host light fixture, and/or the expensive and complexity-introducing design of LED-based solutions that minimize the installation impact to the host light fixture. Often material and manufacturing costs are lost in this trade off.
Power supply requirements of LED-based lighting systems also can complicate installation of LEDs as a retrofit to existing light fixtures. LEDs are low-voltage light sources that require constant DC voltage or current to operate optimally, and therefore must be carefully regulated. Too little current and voltage may result in little or no light. Too much current and voltage can damage the light-emitting junction of the LED. LEDs may be supplemented with individual power adapters to convert AC power to the proper DC voltage, and to regulate the current flowing through during operation to protect the LEDs from line-voltage fluctuations.
A need exists for a can-light retrofit luminaire that may be employed within the volume of space available in an existing light fixture, and that delivers improved lighting quality compared to traditional LED-based solutions. More specifically, a need exists for a can-light lighting solution that benefits from the advantages of digital lighting technology, while exhibiting better cut-off and reduced glare than legacy lamp solutions. Additionally, a need exists for a luminaire designed for ease of installation as well as for manufacturing cost reduction. The lighting industry is experiencing advancements in LED applications, some of which may be pertinent to certain aspects of replacing legacy lamps in can-light lighting fixtures.
U.S. Pat. No. 8,348,492 to Mier-Langner et al. discloses an LED-based luminaire that attaches to a track through magnetic connectors rather than mechanical attachment mechanisms. Multiple puck-shaped luminaires may be mechanically coupled to a non-energized support bar portion of the track, and may be electrically coupled to an electrical conductor portion of the track. However, positioning of the luminaire pucks for lighting effect is limited by the fixed, longitudinal configuration of the track, as well as by reliance on a remote power supply to provide power to each of the luminaires.
U.S. Pat. No. 8,227,813 to Ward discloses an LED-based lighting device for replacing legacy light sources in an existing light fixture having an enclosure that includes a ferromagnetic material. The LEDs are bonded to a heat-conducting substrate that includes a ferromagnetic material that magnetically bonds to the existing light fixture enclosure with sufficient force to carry the light module. However, like the Mier-Langner solution, the Ward design limits positioning of the light sources to the configuration of the substrate, and tethers the light sources to electrical conductors connected to a remote power supply.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.